Showing 15 results for Mollaei
Maedeh Mollaei, Hussein Sadeghi-Namaghi, Hossein Lotfalizadeh, Farzad Minab,
Volume 0, Issue 0 (9-2025)
Abstract
During a laboratory biological study of a midge, Feltiella acarisuga (Vallot, 1827) (Diptera: Cecidomyiidae), acarivorous on two-spotted spider mites, some ceraphronid specimens were reared from the midge cocoons. A detailed morphological study and comparison with previously known species revealed that the ceraphronid is a new species of Aphanogmus Thomson, 1858 (Hymenoptera: Ceraphronidae). The new species is described as A. feltiellophagus Lotfalizadeh, sp. nov. and compared with closely related species. An identification key for all Aphanogmus species associated with predatory cecidomyiids is provided. As a parasitoid of the pupal stage of Feltiella acarisuga, the potential negative impact of A. feltiellophagus on the biological control of tetranychid mites is discussed.
Volume 3, Issue 2 (6-2015)
Abstract
TheChah Nimeh reservoirs of Sistan is as one of the main water sources of Zabol City used for drinking, agriculture, industry and livestock purposes. This study aimed to determine the contribution of the natural and concentration factors of heavy metals such as Cd, Pb and Cu in sediment of Chah Nimeh of Sistan. The concentrations of heavy metals in surface sediments were studied in six stations during 2013. To determine the concentration of the heavy metals atomic absorption spectrometer (Contr AA 700) was used. Sequential extraction analysis was applied based on the share of natural and concentration factor sources of heavy metals. Sequential extraction analysis showed that a considerable part of the Pb (63.67%), Cd (55.17%) and Cu (57.17%) were from natural sources. The highest concentrations of Cd and Pb were 0.81 and 5.57 mg kg-1, respectively, obtained in station one and the maximum Cu concentration was observed in station five (37.8 mg kg-1), while the lowest concentration of Cd, Pb and Cu were 0.34, 3.95 and 31.4 mg kg-1, respectively.
Volume 6, Issue 4 (Fall 2018)
Abstract
Aims: One of the most commonly used applications in forestry is the identification of single trees and tree species compassions using object-based image analysis (OBIA) and classification of satellite or aerial images. The aims of this study were the valuation of OBIA and decision tree (DT) classification methods in estimating the quantitative characteristics of single oak trees on WorldView-2 and unmanned aerial vehicle (UAV) images.
Materials & Methods: In this experimental study Haft-Barm forest, Shiraz, Iran, was considered as the study area in order to examine the potential of Worldview-2 satellite imagery. The estimation of forest parameters was evaluated by focusing on single tree extraction using OBIA and DT methods of classification with a complex matrix evaluation and area under operating characteristic curve (AUC) method with the help of the 4th UAV phantom bird image in two distinct regions. Data were analyzed by paired t-test, multivariate regression analysis, using SPSS 25, Excel 2016, eCognation v. 8.7, ENVI, 5, PCI Geomatica 16, and Google Earth 7.3 Software.
Findings: The base object classification had the highest and best accuracy in estimating single-tree parameters. Basic object classification method was a very useful method for identifying Oak tree Zagros Mountains forest. With using WV-2 data, the parameters of single trees in the forest can extract.
Conclusion: The accuracy of OBIA is 83%. While UAV has the potential to provide flexible and feasible solutions for forest mapping, some issues related to image quality still need to be addressed in order to improve the classification performance.
Volume 14, Issue 3 (11-2024)
Abstract
In recent years, digital transformation has created a revolution in the way companies do business and their relationships with customers, suppliers, and other stakeholders, and has led to the growth of innovation and increased value offered to customers. On the other hand, some organizations, lacking a deep understanding of the concept of digital transformation, consider it a partial and project concept; This is despite the fact that digital transformation is a complex and continuous activity that can significantly affect a company and its activities. In fact, digital transformation can be seen as a deep transformation of business activities, processes and technologies to take advantage of opportunities and changes through a combination of digital technologies. Now, in this article, we are going to examine the digital transformation with the Meta Synthesis method. The present research is applied from the point of view of the goal, and in this research, the Meta Synthesis method and the approach of Barroso and Sandelowski (2007) have been used to review the research literature. The statistical population of the research includes research conducted in the field of digital transformation. The data collection tool is open coding to identify themes and components of digital transformation. In this study, to identify the components of digital transformation, 36 codes were identified as basic themes. Among these, 16 codes were selected as organizing themes and 4 codes were identified and formed as overarching themes with the titles of "planning, soft structures, capabilities, technology and communication".
Volume 14, Issue 12 (3-2015)
Abstract
The main aim of this experiment is to investigate the effects of Nano-size Al2O3 on the mechanical properties and microstructure of multi-passes friction stir welding of Al 2024 lap joint. Nano particles were added into the joint line. A combination of rotational speed and travelling speeds were performed. Optical microscopy and scanning electron microscope were used to investigate the microstructure and fracture surface of samples respectively. Optimum condition (sample) was selected due to highest ultimate tensile strength (UTS). It was seen that sample which included Nano particles and fabricated by 1400 rev/min rotational speed and 16 mm/min travelling speed in second pass of continues welding had improvement in UTS in comparison to one pass welded sample of particle free and after that increasing the number of passes reduce the UTS. The average micro hardness of the sample which was particle rich were increased in comparison to particle free sample in nugget zone. Increasing the number of passes was not effect average micro hardness in nugget zone significantly. Grain sizes were reduced by 2 passes welding and after that no significant reduction has been seen.
Volume 14, Issue 14 (Second Special Issue 2015)
Abstract
The single point incremental forming, which is appropriate for low volume production, is one of the simplest varieties of incremental sheet metal forming process. One of the critical issues with single point incremental forming is excessive thinning which affects the strength of the part and confines the applicability of the process to produce only parts with small wall angle. In this paper, multistage single point incremental forming of a truncated cone with 70° wall angle made from an aluminum alloy sheet is studied to alleviate excessive thinning. By proposing a new two-stage forming strategy and obtaining the corresponding parameters using an appropriate algorithm, it is shown that thinning and forming time can be improved through a systematic design of multistage forming. The implementation of the designed two-stage single point incremental forming leads to less thinning in the part when compared to either the two or three-stage single point incremental forming based on a conventional strategy. The bulging at the bottom of the part, which is one of the drawbacks of multistage single point incremental forming, can also be controlled by using the proposed strategy.
Volume 14, Issue 14 (Second Special Issue 2015)
Abstract
In this research, formability of two layer sheet metals of Al1050 and St12 in single point incremental forming (SPIF) has investigated using numerical and experimental approaches. In order to study the sheet metal formability in this process, the tool paths defined in ABAQUS and CNC machine so that an increasing wall angle is created until the sheet metal reaches its maximum allowable angle and fracture is occurred. Since in this process, the tool exerts local stresses on the sheet metal, 3D simulation of the process is needed. In order to study the effect of process parameters, the analysis is done in three levels of tool radius and vertical step size. In order to derive fracture depth of sheet metal, the force diagram is considered in simulations. It is shown that the outer sheet subjected to higher plastic strains and therefore failure occurred initially at the outer layer. Results also showed that increasing the tool radius and vertical step size speed up process but they have inverse effect on the forming limit angle. For experimentally study and also to validation of simulation results, full factorial experiments with respect to forming speed up to three levels designed and carried out. The difference between FEM and experimental results is about %2.1 in forming limit angle.
Volume 17, Issue 4 (1-2015)
Abstract
Objective: The incidence of breast cancer is approximately one million which makes this cancer one of the most common among women worldwide. Breast cancer comprises 7% of the total death rate caused by cancers. Several strategies that use tumor-associated antigen (TAA) vaccination and early detection of breast cancer are clinically being developed. Breast cancer is caused by increased over expression of certain genes. HER-2 is a tyrosine kinase receptor in the epidermal growth factor family. The role of HER-2 in breast cancer has been extensively studied. HER-2 is found in 25%-30% of breast cancer patients. Herceptin, a human antibody, is used as a therapeutic target for HER-2. The purpose of this study is to produce recombinant protein HER-2 for early detection of breast cancer cells. Methods: We used specific primers to amplify the HER-2 gene. The amplified gene was cloned into pET28a as an expression vector. Cloning was confirmed by restriction analysis and sequencing. Expression was induced using IPTG and the recombinant protein was analyzed by SDS-PAGE. Results: Cloning of the HER-2 gene was confirmed by enzyme digestion and sequencing. The gene was expressed in E.coli BL21 DE3. The pET-28a vector which contained the HER-2 gene showed a high level of expression. The recombinant protein was confirmed by Western blot analysis. Conclusions: A portion of the HER-2 gene was expressed as a recombinant in E.coli. This could be a good diagnostic test for breast cancer.
Volume 17, Issue 9 (11-2017)
Abstract
Forming limit diagram (FLD) is one of the useful tools in the assessment of the sheet formability for designing industrial products. Experimental methods have been developed to determine FLDs. Costly and time-consuming experiments have led to several studies on the use of analytical methods and finite element softwares for predicting FLDs. In the present study, the necking and fracture forming limit curves of AA2024 aluminum alloy sheet were experimentally and numerically obtained through the hemispherical stretching test. Different geometries of the initial blank were considered to create different strain paths. The commercial finite element code Abaqus/Explicit was utilized to simulate experimental tests. Using theoretical equations and experimental results, fracture properties of the aluminum sheet in terms of the equivalent plastic strain at fracture, the stress triaxiality and the Lode angle parameter were captured and implemented in the Abaqus software. In order to capture necking forming limit strains, a numerical criterion based on the major strain variation in the necking zone has been considered. The comparison of the results shows that the numerical model can predict the forming and fracture limit strains with the maximum error of about 6%.
Volume 19, Issue 10 (October 2019)
Abstract
Adsorption simulation of vancomycin antibiotic is done using molecular dynamics. The simulation results show the adsorption behavior of vancomycin on a functionalized biosensor. Regarding the importance of vancomycin, its molecular function is simulated using multiscale discipline. Adsorption to a single assembly monolayer is considered according to vancomycin’s in-vivo function. A selected biosensor is a non-symmetrically functionalized microcantilever which undergoes deformation as a result of changes in surface tension regarding functionalized surface. Multiscale simulations implemented to calculate microcantilever deformation. Molecular models in a vacuum and aquatic media are taken into account. Energy parameters related to surface tension is studied versus the distance of target molecules to the surface of the biosensor. To calculate the distance between receptor molecules in single assembly monolayer, an algorithm is proposed based on experimental results.
Volume 20, Issue 6 (June 2020)
Abstract
Incremental forming of metal sheets is one of the new methods of metal forming with high flexibility in batch production of complex geometries. Due to the absence of a matrix and the gradual applying of forming forces, the forming limit in this process is increased compared to conventional ones. In this research, formability, forming, and finally fracture of aluminum/copper bilayer sheets produced by explosive welding method in the single point incremental forming process are studied. In the numerical prediction of growth and onset of fracture of sheets in this process, the Xue-Wierzbicki damage criterion was used as the VUMAT subroutine in Abaqus software. Using the numerical model, variations of the stress triaxiality and equivalent plastic strain as the variables affecting the damage growth in the incremental forming process were analyzed and explained, and the effect of cyclic and nonlinear loading in this process was shown. Experimental results show a different failure height of various geometries due to different loading conditions. Also, using the verified numerical model, in addition to predicting crack growth location, the fracture height in the formed geometries was predicted by 4.06% difference with respect to the experimental results.
Volume 21, Issue 156 (February 2025)
Abstract
Today, the utilization of smart indicators in food packaging to monitor and detect food quality through analyzing quality data and color changes in packaging films based on the food's condition is on the rise. In this comparative study, halochromic films made of gelatin and k-carrageenan with mirabilis jalapa extract (6, 12, and 24%) and barberry extract (6, 12, and 24%) were developed and examined. Through SEM images and FTIR spectroscopy, it was observed that both types of films incorporating barberry and mirabilis jalapa extracts were uniformly dispersed in the gelatin and k-carrageenan polymer matrix, displaying notable molecular interactions like hydrogen bonding and electrostatic forces. However, films containing mirabilis jalapa extract exhibited more irregular and rough surfaces compared to those with barberry extract. Both types of films displayed good antioxidant properties and responsiveness to changes in pH and ammonia levels. Films with barberry extract demonstrated higher antioxidant activity and greater sensitivity to pH variations. The gelatin and k-carrageenan films with barberry and mirabilis jalapa extracts effectively indicated the freshness of lamb meat stored at 25°C by correlating with the presence of ammonia gases in the storage packages and pH fluctuations. Our results highlight that the structural, physical, and functional attributes of gelatin and k-carrageenan films incorporating pH-responsive extracts are significantly influenced by the extract type and concentration.
Volume 23, Issue 2 (7-2019)
Abstract
In this research, marketing research in Iran has been examined from a methodological point of view, and it seeks to answer the question of whether marketing research is suffering from the myopia in the methods? For this purpose, 1021 articles from 7 major and specialized journals in the field of commerce and marketing have been selected and their articles have been examined in terms of methodology and meta-method in a 10-year period (1387-1396). The results of this study showed that the researches carried out in Iran in the field of marketing have a very small variety of methodology, so that most of the articles were done using structural equation modeling method, with a quantitative tool and questionnaire.
Volume 25, Issue 1 (1-2023)
Abstract
Saffron (Crocus Sativus L.) is a medicinal plant with high nutritional, medicinal value, and anticancer properties that have great cytotoxic effects on cancer cells. To evaluate the anticancer effects of stamen and tepal extracts of saffron on human breast cancer cells (MCF-7), a factorial experiment based on a completely randomized block design with three replications was conducted at the Agricultural Research Field of the University of Birjand, Iran. The treatments included field age (one-, two-, and three-year-old farm), as well as organic and conventional cultivation with different levels of manure and chemical fertilizer (low, medium, and high levels of chemical fertilizer and manure), respectively. The studied traits including Total Phenolic Content (TPC), antioxidant activity, and cytotoxicity were evaluated by using, respectively, 2,2-Diphenyl-1-Picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and A 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenylte- tetrazolium bromide (MTT) tests. The results showed a significant difference among the phytochemical, antioxidant, and anti-cancer properties of the extracts obtained from organic and conventional conditions, the highest of which was obtained from organic cultivation. In addition, the content of antioxidants and therapeutic compounds in the extracts increased by increasing the level of manure. The result of the MTT test showed that both tepal and stamen extracts of saffron had an anti-proliferative effect on cancer cells, with stronger anti-cancer properties for stamen extract. Therefore, the use of stamen extract as an effective and inexpensive source for the pharmaceutical industry would open up new dimensions to prevent the therapeutic challenges of breast cancer.
Volume 30, Issue 4 (Winter 2024)
Abstract
Postcolonial literature is one of the new critical fields that was found in the 1950s and peaked in the late 1970s. One of the most important features of this type of literature is its focus on the colonized, which brings to mind the various manifestations of colonialism. The identity of hybrid and subaltern is one of the main concepts of post-colonial research. In his novel, Radwa Ashour's attention to the challenge between “me” and “other”, the phenomenon of hybridity and identity crisis as well as the conflict of nationals with two-way colonialism, shows the resistance of this pioneer writer against colonialism in the literary form. First of all, the main purpose of this research is to get acquainted with the author's ideology regarding post-colonial issues as well as his fictional works. The research method, criticism and analysis of Granada Trilogy written by Ashour which is based on views of two prominent theorists in the field of post-colonial literature, namely Homi Bhabha and Spivak. The article is based on the assumption that there is a two-way connection between the novel “Granada Trilogy” and post-colonial theories. Although the time gap between the events of this novel and the emergence of this theory is long, it seems that it exemplifies the principles of Homi Bhabha and Spivak. According to the research, cultural conflicts eventually lead to the emergence of a "hybrid" identity, which is in the heart of phenomena such as: "rejection", acceptance, dispersion and imitation. Therefore, in the novel, we see that following the mixing and bonding of Arabs and Gestalts and the emergence of hybrid generations, the pidgin language is spread. Citizens also do not have a fixed identity and undergo transformation according to the existing social conditions.
